Guidelines for management of Bowen's disease: 2006 update

Assessing outcomes of topical 5-fluorouracil as primary and adjuvant therapy for squamous cell carcinoma in-situ

Cutaneous squamous cell carcinoma in-situ (SCCis) is an intraepithelial tumor with a good prognosis. Standard treatment includes both surgical and non-surgical interventions. We determined the clearance rate for SCCis and residual SCCis identified on frozen section during Mohs micrographic surgery (MMS) after treatment with topical fluorouracil 5% cream (5-FU). All MMS cases were initiated for biopsy-proven invasive squamous cell carcinoma (SCC). A retrospective chart review was conducted from January 2017-February 2024 at Columbia University Irving Medical Center (CUIMC) to identify patients with SCCis who were treated with topical 5-FU as primary therapy or adjuvant therapy (AT) for residual SCCis post-MMS for invasive SCC. 41 patients were included (80% males, 70.1 ± 11.8 years). The average follow-up time for the primary therapy group was 25.4 ± 12.8 months, and for the post-MMS AT group 22.5 ± 11.1 months. In the group treated with topical 5-FU as primary therapy (n = 28), 27 patients (96.43%, 95% confidence interval: 81.65-99.91%) achieved complete clearance. One patient had recurrence at 8 months post-treatment. Of the patients in the post-MMS adjuvant treatment group (n = 13), 12 (92.3% clearance, 95% confidence interval 63.97-99.81%) achieved complete clearance. One patient had recurrence at 8 months post-treatment. This study found that topical 5-FU cream is effective as both primary therapy for SCCis and as adjuvant therapy for residual SCCis following MMS of invasive SCC.

Photodynamic Therapy for the Treatment of Bowen's Disease: A Review on Efficacy, Non-Invasive Treatment Monitoring, Tolerability, and Cosmetic Outcome

Bowen's disease represents the in situ form of cutaneous squamous cell carcinoma; although it has an excellent prognosis, 3-5% of lesions progress to invasive cutaneous squamous cell carcinoma, with a higher risk in immunocompromised patients. Treatment is therefore always necessary, and conventional photodynamic therapy is a first-line option. The aim of this review is to provide an overview of the clinical response, recurrence rates, safety, and cosmetic outcome of photodynamic therapy in the treatment of Bowen's disease, considering different protocols in terms of photosensitizers, light source, and combination treatments. Photodynamic therapy is a valuable option for tumors at sites where wound healing is poor/delayed, in the case of multiple and/or large tumors, and where surgery would be difficult or invasive. Dermoscopy and reflectance confocal microscopy can be used as valuable tools for monitoring the therapeutic response. The treatment is generally well tolerated, with mild side effects, and is associated with a good/excellent cosmetic outcome. Periodic follow-up after photodynamic therapy is essential because of the risk of recurrence and progression to cSCC. As the incidence of keratinocyte tumors increases, the therapeutic space for photodynamic therapy will further increase.

Hydrochlorothiazide increases risk of nonmelanoma skin cancer in an elderly Japanese cohort with hypertension: The Shizuoka study

Background

Hydrochlorothiazide (HCT), a widely used hypertensive drug, has photocarcinogenic potential, leading to concerns about the development of nonmelanoma skin cancers (SCs) after intake. Despite substantial numbers of observational studies, the results remain inconsistent especially among Asian countries.

Objective

To assess the incidence of nonmelanoma SCs in hypertensive Japanese HCT users compared with nonusers.

Methods

A population-based, cohort nested, propensity score-matched study was conducted using the Shizuoka Kokuho database. All participants were patients aged ≥60 years. Hazard ratios for SC incidence were calculated in the matched cohorts using the propensity scores of potential confounders, sex, age category, comorbidities, and administration of methotrexate, cyclosporin, and statins.

Results

The risk of SC was higher in HCT users than in nonusers (hazard ratio, 1.58; 95% confidence interval, 1.04-2.40), with preferential sun-exposed location and a tendency to develop squamous cell carcinoma, but not basal cell carcinoma or Bowen disease.

Limitations

No additional information was available from other than medical records. The data were confined to a Japanese population.

Conclusion

HCT use increases the risk of SC in Japanese patients with hypertension and a dark skin type, highlighting the increased risk of SC among HCT users in the aging society worldwide.

Bowen's Disease of the Nipple and Areola: Case Report and Literature Review

Introduction

Bowen's disease (BD) commonly occurs in sites of chronic sunlight exposure such as head, neck and extremities. It rarely distributes on the nipple and areola.

Case Presentation

A 59-year-old female presented with crusted plaque on the right breast for over 1 month. Physical examination found an asymptomatic plaque (5 cm × 5 cm) with irregular shape on the right breast. Histopathological examination suggested irregularly acanthotic epidermis and atypical epidermal cells. Dermis showed inflammatory cell infiltration. Immunohistochemical staining showed negative staining for cytokeratin 7 and cytokeratin 20, and positive staining for Ki67 (60%). The mass was excised and no recurrence occurred in the follow-up. Additionally, we reviewed the literature about BD of the breast and summarized the clinical manifestations, histological features, and treatment options.

Conclusion

We reported a rare BD case involving nipple and areola. Wide local excision and complete nipple excision are effective for patients with BD of the nipple and areola.

An insight into photodynamic therapy towards treating major dermatological conditions

Photodynamic therapy (PDT), as the name suggests is a light-based, non-invasive therapeutic treatment method that has garnered immense interest in the recent past for its efficacy in treating several pathological conditions. PDT has prominent use in the treatment of several dermatological conditions, which consequently have cosmetic benefits associated with it as PDT improves the overall appearance of the affected area. PDT is commonly used for repairing sun-damaged skin, providing skin rejuvenation, curbing pre-cancerous cells, treating conditions like acne, keratosis, skin-microbial infections, and cutaneous warts, etc. PDT mediates its action by generating oxygen species that are involved in bringing about immunomodulation, suppression of microbial load, wound-healing, lightening of scarring, etc. Although there are several challenges associated with PDT, the prominent ones being pain, erythema, insufficient delivery of the photosensitizing agent, and poor clinical outcomes, still PDT stands to be a promising approach with continuous efforts towards maximizing clinical efficacy while being cautious of the side effects and working towards lessening them. This article discusses the major skin-related conditions which can be treated or managed by employing PDT as a better or comparable alternative to conventional treatment approaches such that it also brings about aesthetic improvements thereof.

Analysis on the Effectiveness and Characteristics of Treatment Modalities for Bowen’s Disease: An Observational Study

Treatment options for Bowen’s disease (BD) include surgical excision, cryotherapy, curettage with cautery, topical 5-fluorouracil or imiquimod, and photodynamic therapy. However, it is not clear which treatment is the most effective due to lack of studies. We reviewed the electronic medical records of 158 patients who were diagnosed with BD and treated at Seoul St. Mary’s Hospital from January 2011 to December 2020. Treatment modalities were surgical excision, cryotherapy, photodynamic therapy, and imiquimod. A total of 121 patients was enrolled in this study. The average treatment period was longest for cryotherapy, followed by imiquimod, PDT, and excision (119.53, 87.75, 68.50, and 1 day, respectively). The therapeutic efficacy was highest in the surgical excision group (100%) and lowest in the PDT group (62.5%). The recurrence rate was highest in the imiquimod group (33.33%). Surprisingly, only in patients treated with cryotherapy, satellite lesions developed in 9.09% of them during follow-up. Surgical excision exhibited the highest clearance rate and the lowest recurrence rate, and its treatment period was the shortest, confirming that it remains the gold standard. In contrast, since cryotherapy demonstrated a relatively high recurrence rate including development of satellite lesions, careful monitoring is required when performing cryotherapy for treatment of BD.

The Efficacy of Topical Photodynamic Therapy in Precancerous Lesions of the Skin: A Literature Review

Precancerous skin lesions are associated with high probability of malignant transformation to squamous cell carcinoma. Early detection and management are necessary to improve prognosis and outcomes. Literatures showed that topical photodynamic therapy (PDT) is a promising treatment method which can be successfully applied in several conditions in dermatology. This study aims to review the efficacy of topical PDT for various precancerous lesions in dermatology, such as actinic keratosis, Bowen disease, and Bowenoid papulosis.

Lichen sclerosus of the vulva

Lichen sclerosus of the vulva (LSV) is seen frequently enough to warrant knowing how to diagnose it and institute appropriate treatment strategies. LSV is a chronic skin disorder, very likely of autoimmune origin, which may affect various areas of the perineum, although some women may be affected in extragenital areas. The disease has significant adverse impact on quality of life and sexual activity and may undergo malignant transformation. History of symptomatology and clinical examination is sufficient to make the diagnosis. Skin biopsy is only necessary in specific scenarios. Topical corticosteroids are still the mainstay of therapy, initially to institute remission and then for maintenance. Long-term therapy and surveillance are invariably necessary. Surgery does have a role, but only in specific associated conditions. A number of alternative treatment options have been mooted, especially if the disease is resistant to topical corticosteroids, but these options are still being assessed and studied.

Surgery for Bowen Disease: Clinicopathological Factors Associated With Incomplete Excision

Background

One common treatment for Bowen disease (BD) is surgical excision, but there is no international consensus on the appropriate surgical margins.

Objectives

This study examined what factors affect the rate of incomplete excision of BD.

Methods

Clinicopathological data potentially linked to surgical outcome (complete or incomplete excision) were retrospectively collected from medical and histopathological records on all surgically excised BD lesions diagnosed at Sahlgrenska University Hospital in Gothenburg, Sweden during 2014-2015. Data were analyzed with two definitions of incomplete excision: less strict (ie, BD present at the surgical margin) and strict (ie, dysplasia present at the surgical margin).

Results

In total, 463 BD lesions among 408 patients were included. With the less strict definition, 3 factors were associated with significantly higher rates of incomplete excision: surgical margins <3 mm, a less experienced surgeon, and use of punch biopsy excision. The same factors plus a tumor location on the head and neck area or upper extremities were associated with significantly higher rates of incomplete excision using the strict definition. After adjustment for confounders, less experience was independently associated with incomplete excision using the less strict definition, whereas less experience and location on the head and neck area or upper extremities were independently associated with incomplete excision using the strict definition. Surgeon specialty was not associated with incomplete excision regardless of the definition.

Conclusions

When removing BD surgically, an elliptical excision with surgical margins ≥3 mm carried out by an experienced surgeon should be recommended. Surgical margins may need to be adjusted depending on body site.

Concurrent Bowen's Disease of the Nipple and Breast Cancer

Bowen's disease is a squamous cell carcinoma in situ that commonly develops on the trunk, arms, or legs and has not spread beyond the top layer of skin. It seldom develops on the nipple. We report a patient who presented with Bowen's disease of the nipple and had a concurrent breast cancer identified in the ipsilateral breast after careful examination. Histopathological examination of the surgical specimen after mastectomy confirmed the diagnoses.

Comparison of the recurrence rate of 3 treatment modalities for Bowen disease in an aging city: A retrospective multivariate analysis

A wide range of therapeutic options are available for the treatment of Bowen disease. However, few studies have been conducted on wide excision using various resurfacing methods. The objectives of this study were:One hundred forty-eight lesions were studied. All lesions were histopathologically confirmed as Bowen disease. Lesions were classified by anatomical site and treatment modality and their dimensions were measured. Punch biopsy was reperformed when a treated lesion was considered to have possibly recurred. Recurrence rates were then compared. Preoperative and intraoperative photos and follow-up images were also taken.The most common site of Bowen disease was the head and neck region. Wide excision was found to provide good outcomes with minimal tumor recurrence. Recurrence after cryotherapy occurred relatively quickly (mean 0.2 years, median 0.2 years) while recurrence after wide excision occurred at a mean 2.5 years. Treatment modality was significantly associated with recurrence (P < .05).The optimal treatment for Bowen disease has not been determined. Wide excision provided lower recurrence than other treatment modalities. Providers should be aware of the multiple treatment options available and select the method most appropriate for each patient. The limitations of our study are that it was retrospectively designed and conducted at a single institution.

Human papillomavirus 16-positive penile Bowen's disease involving the distal urethra: A case report

A 79-year-old man visited our hospital with a chief complaint of erythema around the urethral orifice of the glans, and a diagnosis of penile Bowen’s disease was made by penile skin biopsy. Initially, local tumor resection with skin grafting from the femoral skin was performed. However, histopathological examination revealed a positive urethral margin of tumor. Since the degree of urethral lesion of penile Bowen’s disease was unclear, the patient received glansectomy. Histopathological examination revealed a tumor lesion in the distal urethra, 7 mm from the external urethral orifice, and confirmed the complete resection of urethral Bowen’s disease. The patient recovered well, with no definite recurrence of Bowen’s disease up to 13 months after partial penectomy. Human papillomavirus 16 DNA was detected in the paraffin-embedded tumor sample, and in situ hybridization confirmed human papillomavirus 16 DNA locations in the tumor tissue. Immunohistochemistry revealed that p16-INK4a was widely expressed in the tumor tissue.

Non-invasive imaging techniques for the in vivo diagnosis of Bowen's disease: Three case reports

Bowen's disease (BD) is a relatively frequent non-melanoma skin cancer occurring mostly in elderly people. Until now, the usual way to establish the diagnosis is histopathological examination of a skin biopsy. Dermoscopy and reflectance confocal microscopy (RCM) are modern alternative methods that can be used as quick and non-invasive diagnostic techniques and as follow-up instruments in cases in which a conservative treatment is chosen for the management of BD. There are no very specific dermoscopic criteria for the diagnosis of this disease, but some dermoscopic features (scaly surface, vascular structures and pigmentation) can be found more frequent and can be helpful for the diagnosis. RCM of BD shows an acanthotic epidermis with two types of targetoid cells: the first, a large cell with bright center and dark peripheral halo, the second, a cell with dark center and a bright rim surrounded by a dark hallo, related with dyskeratotic cells on histological examination. BD management could be improved by using non-invasive, in vivo imaging techniques that allow a fast and easy diagnosis and can be used as follow-up tools. However, larger studies are necessary for the validation of our observations.

Anal Intraepithelial Neoplasia and Squamous Cell Cancer of the Anus

Anal intraepithelial neoplasia (AIN) is the premalignant condition of the anal squamous tissue. It is associated with the human papilloma virus and is considered the transition prior to the invasive anal squamous cell carcinoma. It is typically asymptomatic and can be either an incidental finding after anorectal surgery or identified when high-risk patient populations are screened. Once AIN is diagnosed, the optimal management remains controversial, partly because the natural history of the disease is unclear. Surgical management of the disease has essentially been replaced by more conservative treatment options and can range from expectant management to topical therapy to photodynamic therapy. The aim of this article is to review the varied treatment options and to briefly review prevention strategies.

High-risk human papillomavirus in a child with digital pigmented Bowen's disease: Case report and dermoscopic findings

Squamous cell carcinoma in situ, also known as Bowen's disease (BD), is a skin malignancy most commonly seen in middle-aged and elderly adults. Pediatric BD is rare and can be a diagnostic challenge for physicians. Digital BD has largely been associated with human papilloma virus. We report an immunocompetent 11-year-old girl with periungual pigmented BD induced by high-risk human papilloma virus.

Epidemiology of skin cancer in the mature patient

Epidermal cancers include keratinocyte cancer, melanocyte cancer, and Merkel cell carcinoma. These cancers account for the vast majority of new cancers diagnosed in Australia, North America, and Europe. Keratinocyte cancer is the most common epidermal cancer and accounts for 7 out of 8 new cancers diagnosed in Australia. Melanoma and Merkel cell carcinoma are less common than keratinocyte carcinoma but are more important causes of mortality in Australia. Keratinocyte cancer has also been demonstrated to be a marker of cancer-prone phenotype. Risk factors for epidermal cancer include intrinsic and environmental factors, in particular exposure to ultraviolet radiation and advanced age. Actinic keratosis has an approximate prevalence of 79% of men and 68% of women between 60 and 69 years of age, and has a low risk of malignant transformation into squamous cell carcinoma. Basal cell carcinoma is the most common malignancy in Caucasians worldwide, with the incidence increasing by 2% per year in Australia. Squamous cell carcinoma is the second most common epidermal cancer, with an incidence of approximately 1035 or 472 per 100,000 person-years in men and women, respectively. Primary risk factors for both basal cell carcinoma and squamous cell carcinoma include light skin color, UV radiation exposure, and chronic immunosuppression. Although the rate of melanoma is increasing, the mortality in Australia is reducing and is currently 9%. The overall incidence of melanoma in Australia is approximately 50 cases per 100,000 persons (62 for men and 40 for women). Keratinocyte carcinoma and melanoma are risk factors for developing further skin cancer and primary malignancy. This contribution reviews the incidence, prevalence, and risk factors associated with the development of epidermal cancer and premalignant epidermal neoplasia.

Anti-retroviral therapy's miracle in the treatment of Bowen's disease in a human immunodeficiency virus-positive patient: A rare case report

Bowen's disease (BD) is a form of squamous cell carcinoma in situ often associated with human papillomavirus. Co-infection with human immunodeficiency virus (HIV) is associated with a greater risk of malignancy. We describe a case of BD in a 52-year-old unmarried HIV-positive male who presented with extensive skin lesions of 1-year duration. Histopathology was suggestive of BD. He had been tried with topical imiquimod cream and cryo-therapy for 6 months. We observed no response for these above therapies. He was started on with anti-retroviral therapy (ART) as his CD4 count was 253 cells/mm³. The entire cutaneous lesions completely disappeared within 6 months of ART, which was an interesting incidence.

The Role of Interleukin-1 in Inflammatory and Malignant Human Skin Diseases and the Rationale for Targeting Interleukin-1 Alpha

Inflammation plays a major role in the induction and progression of several skin diseases. Overexpression of the major epidermal proinflammatory cytokines interleukin (IL) 1 alpha (IL-1α) and 1 beta (IL-1β) is positively correlated with symptom exacerbation and disease progression in psoriasis, atopic dermatitis, neutrophilic dermatoses, skin phototoxicity, and skin cancer. IL-1β and the interleukin-1 receptor I (IL-1RI) have been used as a therapeutic target for some autoinflammatory skin diseases; yet, their system-wide effects limit their clinical usage. Based on the local effects of extracellular IL-1α and its precursor, pro-IL-1α, we hypothesize that this isoform is a promising drug target for the treatment and prevention of many skin diseases. This review provides an overview on IL-1α and IL-β functions, and their contribution to inflammatory and malignant skin diseases. We also discuss the current treatment regimens, and ongoing clinical trials, demonstrating the potential of targeting IL-1α, and not IL-1β, as a more effective strategy to prevent or treat the onset and progression of various skin diseases.

Progression From Perianal High-Grade Anal Intraepithelial Neoplasia to Anal Cancer in HIV-Positive Men Who Have Sex With Men

BACKGROUND

High-grade intraepithelial neoplasia is known to progress to invasive squamous-cell carcinoma of the anus. There are limited reports on the rate of progression from high-grade intraepithelial neoplasia to anal cancer in HIV-positive men who have sex with men.

OBJECTIVES

The purpose of this study was to describe in HIV-positive men who have sex with men with perianal high-grade intraepithelial neoplasia the rate of progression to anal cancer and the factors associated with that progression.

DESIGN

This was a prospective cohort study.

SETTINGS

The study was conducted at an outpatient clinic at a tertiary care center in Toronto.

PATIENTS

Thirty-eight patients with perianal high-grade anal intraepithelial neoplasia were identified among 550 HIV-positive men who have sex with men.

INTERVENTION

All of the patients had high-resolution anoscopy for symptoms, screening, or surveillance with follow-up monitoring/treatment.

MAIN OUTCOME MEASURES

We measured the incidence of anal cancer per 100 person-years of follow-up.

RESULTS

Seven (of 38) patients (18.4%) with perianal high-grade intraepithelial neoplasia developed anal cancer. The rate of progression was 6.9 (95% CI, 2.8-14.2) cases of anal cancer per 100 person-years of follow-up. A diagnosis of AIDS, previously treated anal cancer, and loss of integrity of the lesion were associated with progression. Anal bleeding was more than twice as common in patients who progressed to anal cancer.

LIMITATIONS

There was the potential for selection bias and patients were offered treatment, which may have affected incidence estimates.

CONCLUSIONS

HIV-positive men who have sex with men should be monitored for perianal high-grade intraepithelial neoplasia. Those with high-risk features for the development of anal cancer may need more aggressive therapy.

Non-melanoma Skin Cancer in Canada Chapter 5: Management of Squamous Cell Carcinoma

Background

Squamous cell carcinoma (SCC) is the second-most common form of non-melanoma skin cancer (NMSC).

Objective

To provide guidance to Canadian health care practitioners regarding management of SCCs.

Methods

Literature searches and development of graded recommendations were carried out as discussed in the accompanying introduction (chapter 1 of the NMSC guidelines).

Results

SCCs are sometimes confined to the epidermis, but they can also invade nearby tissues and, in some cases, metastasize to neighbouring lymph nodes or other organs. This chapter discusses the natural history, staging, prognosis, and management of SCC—a tumour type that is less common but typically more aggressive than BCC. For this reason, margin control is strongly preferred in treating SCCs.

Conclusions

Although approaches such as cryosurgery and radiation therapy may be considered for some patients, surgical excision—sometimes coupled with radiation—remains the cornerstone of SCC management. Patients with high-risk SCC may also be considered for referral to an appropriate multidisciplinary clinic.

Treatment of Bowen Disease With Photodynamic Therapy and the Advantages of Sequential Topical Imiquimod

Photodynamic therapy (PDT) has been shown to be useful and effective in the treatment of actinic keratosis, Bowen disease, and basal cell carcinoma. We present a series of 13 Bowen disease lesions treated using PDT. Complete responses were achieved in 11 (84%) of the lesions after 3 months of treatment; at 18 months, complete responses were seen in 9 (70%) of the lesions. Patients who presented a partial response or recurrence were treated with topical 5% imiquimod and achieved complete responses. The lesions that presented partial response or recurrence were the largest lesions, between 3 and 5cm in diameter. PDT in monotherapy or combined sequentially with imiquimod is an excellent and well-tolerated therapeutic option for Bowen disease. The treatment has few adverse effects and shows satisfactory results, particularly in multiple large lesions in areas of difficult surgical reconstruction or in elderly patients with a high surgical risk.

Development of poorly differentiated invasive squamous cell carcinoma in giant Bowen's disease: a case report with dermatoscopy

Bowen’s disease (BD) is an in situ form of squamous cell carcinoma (SCC), often occurring in the chronically UV-damaged skin of elderly people. The risk of progression of BD to invasive SCC varies between 3% and 5%, and one-third of invasive tumors may metastasize. Herein we discuss the dermatoscopic findings of a case of giant Bowen’s disease, which progressed to poorly differentiated invasive SCC.

Successful Treatment of Extensive Squamous Cell Carcinoma of the Conjunctiva and Upper Eyelid Skin With Topical Therapy Alone

This study reports a case of extensive periocular squamous cell carcinoma of the conjunctiva, extending into the superior fornix, over the upper eyelid margin, and involving the superficial layers of the eyelid skin up to the eyebrow, that was successfully treated solely with topical therapy.

Medical interventions for high-grade vulval intraepithelial neoplasia

BACKGROUND

This is an updated version of a review first published in theCochrane Database of Systematic Reviews, Issue 4, in 2011. Vulval intraepithelial neoplasia (VIN) is a pre-cancerous condition of the vulval skin and its incidence is increasing in women under 50 years. High-grade VIN (also called usual-type VIN (uVIN) or VIN 2/3 or high-grade vulval intraepithelial lesion) is associated with human papilloma virus (HPV) infection and may progress to vulval cancer, therefore is usually actively managed. There is no consensus on the optimal management of high-grade VIN; and the high morbidity and relapse rates associated with surgical interventions make less invasive interventions highly desirable.

OBJECTIVES

To evaluate the effectiveness and safety of medical (non-surgical) interventions for high-grade VIN.

SEARCH METHODS

We searched the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 3), MEDLINE and EMBASE (up to 30 March 2015). We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included studies and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that assessed non-surgical interventions in women diagnosed with high-grade VIN.

DATA COLLECTION AND ANALYSIS

We used Cochrane methodology with two review authors independently abstracting data and assessing risk of bias. Where possible, we synthesised data in meta-analyses using random effects methods.

MAIN RESULTS

Five trials involving 297 women with high-grade VIN (defined by trial investigators as VIN 2/3 or VIN 3 or 'high-grade' lesions) met our inclusion criteria: three trials assessed the effectiveness of topical imiquimod versus placebo; one assessed topical cidofovir versus topical imiquimod; and one assessed low- versus high-dose indole-3-carbinol in similar types of participants. Three trials were at a moderate to low risk of bias, two were at a potentially high risk of bias.Meta-analysis of the three trials comparing topical imiquimod 5% cream to placebo found that women in the active treatment group were more likely to show an overall response (complete and partial response) to treatment at five to six months compared with the placebo group (Risk Ratio (RR) 11.95, 95% confidence interval (CI) 3.21 to 44.51; participants = 104; studies = 3; I(2) = 0%; high-quality evidence). A complete response at five to six months occurred in 36/62 (58%) and 0/42 (0%) participants in the active and placebo groups, respectively (RR 14.40, 95% CI 2.97 to 69.80; participants = 104; studies = 3; I(2) = 0%). A single trial reported 12-month follow-up, which revealed a sustained effect in overall response in favour of the active treatment arm at 12 months (RR 9.10, 95% CI 2.38 to 34.77; moderate-quality evidence), with 9/24 (38%) and 0/23 (0%) complete responses recorded in the active and placebo groups respectively. Progression to vulval cancer was also documented in this trial (one versus two participants in the active and placebo groups, respectively) and we assessed this evidence as low-quality. Only one trial reported adverse events, including erythema, erosion, pain and pruritis at the site of the lesion, which were more common in the imiquimod group. Dose reductions occurred more frequently in the active treatment group compared with the placebo group (19/47 versus 1/36 participants; RR 7.77, 95% CI 1.61 to 37.36; participants = 83; studies = 2; I(2) = 0%; high-quality evidence). Only one trial reported quality of life (QoL) and there were no significant differences between the imiquimod and placebo groups.For the imiquimod versus cidofovir trial, 180 women contributed data. The overall response at six months was similar for the imiquimod and cidofovir treatment groups with 52/91 (57%) versus 55/89 (62%) participants responding, respectively (RR 0.92, 95% CI 0.73 to 1.18). A complete response occurred in 41 women in each group (45% and 46%, respectively; RR 1.00, 95% CI 0.73 to 1.37). Although not statistically different, total adverse events were slightly more common in the imiquimod group of this trial with slightly more discontinuations occurring in this group. Longer term response data from this trial are expected.The small trial comparing two doses of indole-3-carbinol contributed limited data. We identified five ongoing randomised trials of various interventions for VIN.

AUTHORS' CONCLUSIONS

Topical imiquimod appears to be a safe and effective treatment for high-grade VIN (uVIN), even though local side-effects may necessitate dose reductions. However, longer term follow-up data are needed to corroborate the limited evidence that response to treatment is sustained, and to assess any effect on progression to vulval cancer. Available evidence suggests that topical cidofovir may be a good alternative to imiquimod; however, more evidence is needed, particularly regarding the relative effectiveness on longer term response and progression. We await the longer-term response data and the results of the five ongoing trials.

Non-melanoma Skin Cancer in Canada Chapter 1: Introduction to the Guidelines

BACKGROUND

Non-melanoma skin cancer (NMSC), including basal and squamous cell carcinoma, represents the most common malignancy.

OBJECTIVE

The aim of this document is to provide guidance to Canadian health care practitioners on NMSC management.

METHODS

After conducting a literature review, the group developed recommendations for prevention, management, and treatment of basal cell carcinomas, squamous cell carcinomas, and actinic keratoses. These tumour types are considered separately in the accompanying articles. The Grading of Recommendations Assessment, Development and Evaluation system was used to assign strength to each recommendation.

RESULTS

This introduction describes the scope and structure of the guidelines and the methods used to develop them. The epidemiology of NMSC is reviewed, as are the pathophysiologic changes occurring with damage to the skin, which lead to the formation of actinic keratoses and invasive squamous or basal cell carcinomas.

CONCLUSIONS

This introduction describes the need for primary prevention and offers an overview of treatment options that are discussed in later chapters of the guidelines.

Bowen's disease with features resembling myrmecia wart

We report the clinical and pathological findings of two cases of Bowen's disease (BD) with features resembling myrmecia wart, and tried to find evidence of human papillomavirus (HPV) infection in such lesions by immunohistological staining, genotyping systems, polymerase chain reaction (PCR) and electron microscopy. Both cases manifested unique barnacle-like hyperkeratotic nodules or plaques clinically, and microscopically proliferation of atypical keratinocytes involving the entire thickness of the epidermis, hypergranulosis with eosinophilic and/or basophilic inclusion bodies, features that mimicked myrmecia wart. Electron microscopy revealed myrmecia inclusion-like large intranuclear and cytoplasmic electron-dense bodies. Immunohistological staining with anti-HPV antibody, genotyping systems for HPV infection and specific PCR designed to detect HPV-1 L1 sequences failed to detect evidence of HPV infection. P16(INK4a) was overexpressed in the atypical keratinocytes of both cases. This finding suggests that the pathogenesis of these two BD may involve certain unknown or undetectable HPV, or reflect disturbances of the Rb signaling pathway unrelated to HPV infection. The unique "myrmecioid" clinicopathological features in our cases suggest that this type of lesion may be a new variant of BD.

Reflectance confocal microscopy: non-invasive distinction between actinic keratosis and squamous cell carcinoma

BACKGROUND

Early recognition of squamous cell carcinoma (SCC) is difficult. Non-invasive reflectance confocal microscopic (RCM) imaging of the skin is a promising diagnostic technique. Although several RCM features for SCC and AK have been described, it is not determined whether RCM has the ability to distinguish between SCC and actinic keratosis (AK).

OBJECTIVE

To determine in vivo reflectance confocal microscopic features that are specific for making a distinction between AK and SCC.

METHODS

In 24 patients, 30 lesions clinically suspicious for AK or SCC were selected for RCM imaging. Following the imaging procedure, a 3 mm skin biopsy was obtained for confirmation of the histopathological diagnosis. Two observers evaluated the RCM images according to a literature based list of RCM features. The obtained data were evaluated by an univariate and forward multivariate logistic regression analysis, kappa analysis and independent T-test.

RESULTS

The univariate logistic regression showed statistically significant odds ratios for several RCM features, including architectural disarray in the stratum granulosum, architectural disarray in the spinous layer and nest-like structures in the dermis. The forward multivariate logistic regression analysis showed that the combination of these features increased the ability to make the correct diagnosis AK and SCC non-invasively. The interobserver agreement between a starting and an experienced RCM observer ranged from poor to no agreement.

CONCLUSION

This study revealed specific RCM features that can distinguish between AK and SCC, stimulating further prospective, large cohort research in this field. This will result in correct, efficient and adequate diagnosis and treatment of clinically difficult to distinguish AK and SCC lesions.